On Thu, Apr 13, 2017 at 08:37:50PM +0530, Harsh Jain wrote:
> On Thu, Apr 13, 2017 at 8:20 PM, Christophe JAILLET
> <christophe.jaillet@xxxxxxxxxx> wrote:
> > Le 13/04/2017 à 16:04, Dan Carpenter a écrit :
> >>
> >> On Thu, Apr 13, 2017 at 02:14:30PM +0200, Christophe JAILLET wrote:
> >>>
> >>> If 'chcr_alloc_shash()' a few lines above fails, 'base_hash' can be an
> >>> error pointer when we 'goto out'.
> >>> So checking for NULL here is not enough because it is likely that
> >>> 'chcr_free_shash' will crash if we pass an error pointer.
> >>>
> >>> Signed-off-by: Christophe JAILLET <christophe.jaillet@xxxxxxxxxx>
> >>> ---
> >>> Another solution, amybe safer, would be to instrument 'chcr_free_shash'
> >>> or
> >>> 'crypto_free_shash' to accept an error pointer and return immediatelly in
> >>> such a case.
> >>> ---
> >>> drivers/crypto/chelsio/chcr_algo.c | 2 +-
> >>> 1 file changed, 1 insertion(+), 1 deletion(-)
> >>>
> >>> diff --git a/drivers/crypto/chelsio/chcr_algo.c
> >>> b/drivers/crypto/chelsio/chcr_algo.c
> >>> index f19590ac8775..41750b97f43c 100644
> >>> --- a/drivers/crypto/chelsio/chcr_algo.c
> >>> +++ b/drivers/crypto/chelsio/chcr_algo.c
> >>> @@ -2351,7 +2351,7 @@ static int chcr_authenc_setkey(struct crypto_aead
> >>> *authenc, const u8 *key,
> >>> }
> >>> out:
> >>> aeadctx->enckey_len = 0;
> >>> - if (base_hash)
> >>> + if (!IS_ERR_OR_NULL(base_hash))
> >>> chcr_free_shash(base_hash);
> >>
> >> Ah... Ok. Fine, but redo the first patch anyway because it shouldn't
> >> ever be NULL.
> >>
> >> regards,
> >> dan carpenter
> >
> > Hi Dan,
> >
> > I will update the first patch as you proposed in order to:
> > - teach 'chcr_alloc_shash' not to return NULL
> > - initialize 'base_hash' with ERR_PTR(-EINVAL)
> > - update the above test to !IS_ERR.
> > The 2 patches will be merged in only 1.
> >
> > Thanks for your suggestions.
>
> Thanks for pointing the error. or You can simply return instead of
> goto. Just like that.
>
> 1.3 @@ -2455,7 +2455,8 @@ static int chcr_authenc_setkey(struct cr
> 1.4 base_hash = chcr_alloc_shash(max_authsize);
> 1.5 if (IS_ERR(base_hash)) {
> 1.6 pr_err("chcr : Base driver cannot be loaded\n");
> 1.7 - goto out;
> 1.8 + aeadctx->enckey_len = 0;
> 1.9 + return -EINVAL;
Don't do that. There should be a goto.
regards,
dan carpenter
